The application generally relates to an electromagnetic relay. The application relates more specifically to an electromagnetic relay having a relay actuator with an adjustment dial for setting an overtravel adjustment for electrical contacts.
A relay is an electromagnetically actuated electrical switch. Conventional relays include stationary contacts and moving contacts corresponding with the stationary contacts. When the relay is electromagnetically actuated, the moving contacts engage or disengage with the stationary contacts, to respectively close or open an electrical circuit.
A conventional relay has a base structure, a housing, a relay coil, an armature, a pusher and a contact system. The base structure and housing are made of an electrically insulating material and support and enclose the operative electromagnetic parts of the relay. The relay coil has a coil and a magnetically permeable core connected to the tilting armature to move the armature. The coil is a cylindrical hollow member with a rectangular internal cross section corresponding to a cross section of the core, and is spring loaded to return to a specified position when the coil is de-energized. The pusher links the tilting armature and the contact system and transfers the coil force applied to the armature to the contact system.
In manufacturing, the relay stationary contact springs and moving contact springs are set to make contact concurrently when closing. Both the moving and stationary springs include metallic pads or tips, i.e., electrical contacts, which serve as the mutual point of contact. The spring contacts absorb wear and tear caused by the actuation force, electrical arcing, repetitious movements, and other deteriorating factors. To account for this deterioration due to repeated use, an over-travel adjustment is provided in manufacturing. This process involves manipulating the contact springs, which are generally made from copper, copper alloy or similar conductive material. The contact springs must be bent, turned, twisted or otherwise manipulated to attempt to set a uniform overtravel position for the multiplicity of contact springs. Due to the mechanical properties of the metallic contact springs, it is difficult to achieve a reliable and precise overtravel setting.
There is a need for an apparatus and system for automatically achieving a uniform overtravel adjustment for contact springs in an electromagnetic relay.
Intended advantages of the disclosed systems and/or methods satisfy one or more of these needs or provides other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments that fall within the scope of the claims, regardless of whether they accomplish one or more of the aforementioned needs.